Noncombustible, building construction typically is of one of five basic structural types or combinations thereof: 1) reinforced concrete frame; 2) reinforced wall bearing masonry; 3) structural steel framework; 4) precast concrete framework; or 5) light gage steel bearing wall. Each of these methods of construction is subject to cost disadvantages due to one or more of: time, labor, materials, weight, and complexity of assembly. Reinforced concrete frame construction requires the on site labor and time to build forms for the wet concrete, waiting for it to harden, and then time and labor to remove the used forms. Thereupon, the building is completed and finished on site with expensive job site labor and materials. Reinforced wall bearing masonry uses concrete block walls held together with mortar, then reinforced with steel rods and filled with concrete to produce the bearing walls. This approach is used extensively in residential construction but is limited to a few stories high. The biggest disadvantage has to do with adding plumbing, wiring and finishing material with job site labor, at prime cost. Structural steel or pre-cast concrete framework construction is commonly used in high-rise work, but require the heavy steel or concrete supporting frame structure; the ceilings, walls and all the interiors and exteriors to be completed and finished with on site labor and materials, a costly construction.
Light gage steel bearing wall construction employs framing partitions of light gage steel members assembled into panels. These members are load bearing and can be assembled into panels at the job site, prior to erection, but can be assembled more economically in a controlled factory environment. However, the remainder of the building then is completed and finished with costly job site labor and materials.
U.S. Pat. No. 4,409,764 by Wilnau discloses a system for constructing the structural framework of a building or other structure of reinforced concrete that is characterized by column and beam forms of sheet metal which remain in place as permanent parts of the framework after being filled with concrete. These forms are factory-assembled, together with the necessary internal metal reinforcing skeletons, and shipped to the building site ready for erection of the column forms and interconnection thereof by the beam forms. When the column and beam structure is complete, the curtain walls must be assembled and finished on site. This current invention describes a system of load bearing walls which function as curtain walls as well as the super structure.
U.S. Pat. No. 5,048,257 by Luedtke discloses a method of constructing multiple story buildings, particularly detention structures, whereby the framing members are lightweight steel channel members that are generally similar and in certain applications, interchangeable. The walls and floors of the building are framed with the channel members and lathe sheathing is applied, with cementitious fill there between. This specification does explain a stay in place forming system. It describes the placement of the fill as being observed through the lath to assure a solid fill. Luedtke later explains the subsequent application of cement plaster or stucco like material. This terminology necessarily infers that the plaster or stucco like material is applied after the concrete has cured, possibly to assure a straight wall that bowed during the placement of plastic concrete. The Luedtke design discusses a method of concrete delivery consisting of a fill hose as pictured in FIG. 6 of the patent. This practice is not practical and probably not possible, at least not at the low slump mentioned and required to achieve the strength provided by the proper water to cement ratio.
While both Wilnau and Luedtke combine the advantages of reinforced concrete and steel framework by using portions of the steel framework as non-removable forms for the poured concrete columns and beams, these inventions do not take full advantage of the efficiencies and cost savings that can be obtained by factory prefabrication of not only the structural wall panel, but also of the window casings and door jambs contained in the wall panels that also serve as an integral form for receiving the poured concrete. Further, these inventions do not take advantage of the cost-savings that can be achieved by factory pre-finishing the wall panels with plaster or stucco like material and paint or wallpaper.
Another invention, U.S. Pat. No. 3,983,368 by Perrin discloses an invention whereby a wall is formed as by spraying cementitious material through and around two panels of sheet material thus to produce a composite wall with a hollow core therebetween, such core to be filled with a rigid material. This design is a sandwich panel where the core is described as a cellulostic material referred to as corrugated paperboard or cardboard. The voids within the core appear to be very small at least as compared to the current invention which is a forming system for achieving conventional steel reinforced concrete in a more economical fashion. Although Perrin's wall panel contemplates a sprayed plaster or stucco like material finish, just as in Wilnau and Luedtke, it also does not take advantage of prefabricating window and door jambs as an integral part of the framing structure. Further, Perrin's invention relies on the use of a reinforced rigid core for its load-bearing properties. While suitable for residential housing, such construction will not provide the load-bearing capacity that the use of conventional steel reinforced concrete provides as disclosed in the present invention.
The Anderson U.S. Pat. No. 5,996,293 describes a window buck devoted to providing an opening. The current invention does define an opening but the hollow metal jamb also functions as an integral part of the structural framework, provides a stop for the mounting of doors and windows and is ideally suited as a termination device for the finished surfaced surfaces.